For example, by a system for delivering an appropriate advertisement according to user's attributes and/or status such as a behavioral targeting advertisement system, preferable advertisements are delivered to the user.
In such a system, it is requested that the contents are delivered and displayed in real time. For example, when the advertisement is displayed at a vending machine provided in the station precincts, the user watches the panel only several seconds. Therefore, when a following sequential processing has not been completed within several seconds, the user does not watch it. More specifically, when a user identifier (ID) is inputted, the contents to be displayed are determined, and the contents are delivered to the vending machine to display the contents on a display device of the vending machine.
However, when the contents to be displayed are determined to deliver the determined contents to the vending machine by using server resources, which are remotely disposed in one data center, the delay of the communication, the congestion of the network due to the traffic concentration, and the heavy load on the servers are problems.
In order to solve the problems, an application of a distributed cache technique is considered. For example, plural cache servers connected to plural clients and a control server for controlling the plural cache server are provided in a system. Then, the control server predicts data to which an access will be requested in future by the cache server, and copies the predicted data to the cache server that has not requested to access the predicted data, yet. By carrying out such a processing, the access to the data is carried out at high speed, and the load of the server is reduced. However, because the access history is used to carry out the prediction, the contents to which no access has been made are not copied to the cache server. When the contents, which are not copied, are displayed, the contents, which are stored in a remote location, are obtained and displayed. Therefore, it takes a long time.
On the other hand, a technique exists to provide community information that matches a user more by considering the respective user's community-oriented degree and/or visiting schedules or other user's profile and/or interests and preferences. More specifically, (A) position information of a moving person or object and time information are simultaneously obtained, (B) a moving range having a time axis is extracted from sets including the obtained position information and time information, (C) the community information is obtained, (D) the moving range information is matched with the community information, and (E) the matched information is displayed.
Furthermore, an advertisement delivery system is known that has plural display device to display advertisements, and an advertisement delivery apparatus that selects an advertisement for a user based on information concerning purchase history stored in a portable terminal of the user and delivers the selected advertisement to the display device. In this system, the display device receives information including the purchase history from the user's portable terminal, which is adjacent to the display device, and sends the received information as the purchase history and user position information representing the user's location to the advertisement delivery apparatus. The advertisement delivery apparatus receives the purchase history and user's position information from the portable terminal, analyzes plural items in the purchase history, and extracts information concerning products to be displayed as the advertisement from the purchase history. Then, the advertisement delivery apparatus selects a product to be displayed as the advertisement from information of the extracted products, and obtains the advertisement relating to the product from an advertisement repository storing advertisement contents. After that, the advertisement delivery apparatus determines a display device that will be next adjacent to the user, based on the user position information, and sends the advertisement contents obtained from the advertisement repository to the determined display device. However, this does not consider the utilization of the cache, and a problem concerning the delay of the display occurs.
In other words, there is no conventional technique for caching the contents that may be displayed to the user in an early stage.